How do you express the 26 letters of the alphabet with only the on/off sputtering of electrical current? James Gleick writes in his book The Information that solving that puzzle "taxed [Samuel F. B. Morse's] ingenuity more than any mechanical problem of the telegraph. It is fitting that history attached Morse's name to his code, more than to his device." Morse initially thought to send numbers, digit by digit, with each number corresponding to a word. Operators would have to look up each number in a special dictionary. Later he, along with his assistant Alfred Vail, honed in on the system of dots and dashes that became standard. Above, an early effort at that code, from around 1837, appears on the bottom line, labeled "2d For Letters."
Below, recent Pictures of the Day:
Image: Library of Congress.